4G/5G网络融合演进探析

随着5G SA网络的商用部署,5G与4G协同演进是运营商十分关心的迫切问题。首先,分析了EPC网络为何将长期存在,提出5GC与EPC融合组网是移动核心网的中长期架构,随后,重点分析EPC网络如何与5GC网络协同演进发展,探讨了MME、DRA等EPC网元的演进路径,同时考虑了后续EPC网络的部署形态,为未来的移动网络演进做出有益的探讨。     

广电行业如何借助5 G技术实现创新发展

就已经拥有5 G商用牌照的广电行业,如何发挥自身资源优势,借助5 G技术加快推进商用服务,以此创新内容运营模式、服务模式、商业模式,突出个性化服务,加速升级广电产业链,提升广电网络承载力,以精准化服务来吸引用户、留住用户、打开边界,实现创新融合发展进行了探讨。     

5G技术的趋势与发展关键

5G技术是4G后的下一代通信技术,目前处于探索阶段,具有广阔的应用空间。根据国内外技术发展的新趋势、新动态,对5G技术的未来发展进行分析,阐述其关键技术,同时介绍国内最新的发展情况。     

一种4G/5G协同精准规划方法的研究

在现有4G网络的基础上,通过深入洞察4G高价值区域,聚焦三高用户集群,兼顾夯实4G网络覆盖,从而精准确定5G发力区域。通过编制合理预算,精确投资,获得最大收益比与品牌凝聚力的提升,为拓宽市场营销渠道打下坚实基础。本项目研究最大的技术特点是从容量、覆盖两个维度进行4/5G协同规划方法研究。基于4G网络存在的覆盖黑点以及容量不足区域,通过规划5G站点反补4G,借助AAU开通3D-MIMO以及规划建设锚点站等手段最大化提升4G网络质量。同时通过4G网络评估指导5G精准建设,从而最大限度的提升投资收益比。     

基于时延感知的5G通信链路映射算法

现有5G通信算法存在兼容性差,误码率高等问题,导致数据传输频谱效率和峰值速率较低。因此提出基于时延感知的5G通信链路映射算法。该算法通过线性预编码技术传输数据,对数据预先处理,进而设计5G通信链路的层映射模式,完成数据到端口的处理,最后基于时延感知优化映射算法感知层,实现对5G通信链路映射算法的优化。实验结果表明,与传统算法相比,数据传输的频谱效率和峰值速率均有所提升,总体数据传输效果提升19.8%。由此可见,基于时延感知的5G通信链路映射算法具有更高效的数据传输效果。     

A GPU‐Adapted Structure for Unstructured Grids

A key advantage of working with structured grids (e.g., images) is the ability to directly tap into the powerful machinery of linear algebra. This is not much so for unstructured grids where intermediate bookkeeping data structures stand in the way. On modern high performance computing hardware, the conventional wisdom behind these intermediate structures is further challenged by costly memory access, and more importantly by prohibitive memory resources on environments such as graphics hardware. In this paper, we bypass this problem by introducing a sparse matrix representation for unstructured grids which not only reduces the memory storage requirements but also cuts down on the bulk of data movement from global storage to the compute units. In order to take full advantage of the proposed representation, we augment ordinary matrix multiplication by means of action maps, local maps which encode the desired interaction between grid vertices. In this way, geometric computations and topological modifications translate into concise linear algebra operations. In our algorithmic formulation, we capitalize on the nature of sparse matrix‐vector multiplication which allows avoiding explicit transpose computation and storage. Furthermore, we develop an efficient vectorization to the demanding assembly process of standard graph and finite element matrices.     

高耐蚀哈氏合金G-30的性能及应用

评述了高铬镍基哈氏合金Ｇ３０的化学成分、力学性能、耐蚀性能及冷热加工性能,并结合使用情况分析了它的应用前景。     

重要的半合成头孢菌素中间体--7-ADCA

7-氨基-3-去乙酰氧基头孢烷酸(7-ADCA)是以青霉素G为原料,经氧化、扩环重排、裂解3步反应制得.目前用于裂解反应的固定化酰化酶技术日益成熟,因而化学法裂解的生产工艺已逐渐被淘汰.世界上主要生产厂家有荷兰GIST公司、美国TEVA公司、意大利DOBFA公司、台湾骏祥公司和印度LUPIN公司等.国内华北制药倍达公司开发了酶法生产7-ADCA的工艺,并建立了250t/a的生产能力,产品质量与进口产品相当.我国7-AD-CA年需求量约900t,而生产能力不足300t/a.国内企业应改进回收工艺、降低生产成本、实现规模化生产,以改变市场依赖进口的局面.     

GPCR antitarget modeling: pharmacophore models for biogenic amine binding GPCRs to avoid GPCR-mediated side effects

G protein-coupled receptors (GPCRs) form a large protein family that plays an important role in many physiological and pathophysiological processes. However, the central role that the biogenic amine binding GPCRs and their ligands play in cell signaling poses a risk in new drug candidates that reveal side affinities towards these receptor sites. These candidates have the potential to interfere with the physiological signaling processes and to cause undesired effects in preclinical or clinical studies. Here, we present 3D cross-chemotype pharmacophore models for three biogenic amine antitargets: the alpha(1A) adrenergic, the 5-HT(2A) serotonin, and the D2 dopamine receptors. These pharmacophores describe the key chemical features present within these biogenic amine antagonists and rationalize the biogenic amine side affinities found for numerous new drug candidates. First applications of the alpha(1A) adrenergic receptor model reveal that these in silico tools can be used to guide the chemical optimization towards development candidates with fewer alpha(1A)-mediated side effects (for example, orthostatic hypotension) and, thus, with an improved clinical safety profile.     

Inhibition of potato cyst nematode hatch by lignans fromBupleurum salicifolium (Unbelliferae)

A series of lignans fromBupleurum salicifolium Soland (Umbelliferae) were tested for nematostatic activity on the cysts and freed secondstage juveniles of the potato cyst nematodesGlobodera rostochiensis andG. pallida. None of the six lignans tested—bursehernin, matairesinol, syringaresinol, the novel product buplerol, guayarol, and a derivative, nortrachelogenin triacetate—showed nematicidal activity in an in vitro analysis with second-stage juveniles, but significant differences were noted when the lignans were assayed for nematostatic activity as cyst hatching inhibitors. Bursehernin and matairesinol showed the greatest activity, at concentrations of 50 ppm. This is the first known instance of a natural product inhibiting the hatch of the nematodeG. pallida. The HID (hatching inhibiting dose) of bursehernin was estimated, and some conclusions were drawn about the structure-activity relationships of the lignans under study.